Shock-absorber for percussion-operated tools.



G. COOK.

SHOCK ABSORBER FOR PERCUSSION OPERATED TOOLS.

APPLICATION FILED SEE-1.2, 1913,

1,093,830. Patented Apr. .21, 1914 A TTOR/VEY GEORGE oooK, or SIOUX CITY, IOWA.

SHOCK-ABSORBER FOR PERCUSSION-OPERATED TOOLS.

Specification of Letters Patent.

Patented A li-.21, 1914.

Application filed September 2, 1913. Serial No. 787,718.

applied to the work, causes the latter to con stantly rebound from the work. The vibration thus set up in the driven tool, and thereby imparted to the hammer, is attended with evils chiefly as follows: The hammer is subjected to excessive wear; constant strain is imposed upon the operator which makes his work arduous and difficult; and

accurate work cannot be performed with rapidity.

The invention has, therefore, for its pri-' mary object, the production of an appliance particularly adapted for use in connection with a pneumatic hammer, whereby the vibration'and attendant evils are eliminated.

Another object of my invention is the construction of a device of this sort thoroughly efficient in operation yet simple and inexpensive in production.

'A further object is the construction of a shock-absorbing device which may be employed with divers kinds of percussiondriven tools.

With these and other objects in view, the invention, consisting in the construction, combination and novel arrangement of parts, will be fully understood from the following description reference being had to the accompanying drawings which form a part of this application and in which like characters of reference indicate corresponding parts throughout the several views, of which, Figure 1 is a longitudinal section of the barrel of a pneumatic hammer equipped with a device constructed in accordance with my invention; Fig. 2 is a side elevation of the barrel threaded into the casing of my device, the latter being broken away; Fig. 3

is an end elevation of the device; Fig. 1 isaway; and Fig. 6 is a side elevation of the I internal nut.

I illustrate and herein describe an embodiment of my invention particularly adapted for use with pneumatic hammers yet I donot wish to be understood as being limited to the specificform or application selected for illustration, for, without departing from the spirit of the invention the device may be modified in various ways to accommodate different classes of tools.

Referring to the illustrations 7 represents the barrel of a pneumatic hammer within which reciprocates the plunger, 8. 9 is. a chisel held freely within the end of the barrel and adapted to receive the blows from the plunger. The shank of the chisel is reduced affording, as usual, a shoulder, 10, which prevents inward displacement of the too The device of my invention encircles the tool intermediate the shoulder 10 and the barrel and comprises a casing, 11, preferably cylindrical and provided with a bore, 12, and a counter-bore, 13, forming an annular shoulder, 14, which serves as a-normal-stop for a movable flanged-collar, 15, which encircles the tool 9 and is adapted for engagement with the shoulder thereof. In the opposite end of the casing is an annular rim, 16, which is preferably threaded into the casing, as illustrated, and encircles the shank of the tool. The movabletool-seat, 15, is yieldable inwardly by virtue of a compression-spring, 17, interposed between the said seat and the rim, or internal nut, 16.

' If desired the casing may be formed integrally with the barrel or the barrel reduced and externally-threaded to receive the casing as shown in Fig. 2; and when thus attached the presence of the rim 16 is arbitrary in asmuch as the compression means, 17 may seat upon the barrel end.

The operation of my device is readily apparent. By its application no obstruction is presented to the outward movement of the driven tool, yet as the tool rebounds sudden shock is prevented by engagement of the tool with the yieldable seat. I

Having thus described my inventiomwhat I claim as new and desire to secure by Letters Patent, is, 4

A shock absorber for percussion-operate tools having reduced shanks and shoulders afforded thereby, said shock absorber comprising an open ended adapted to freely encircle the shanks of the tools and having an internal shoulder in one end thereof and threaded at the opposite end; a collar freely inclosed by said casing, adapted to receive the shanks and engage the shoulders of the tools and having a flange to engage said internal shoulder; a nut engaged with the threaded end of the cylindrical casing casing; and a compression spring interposed 10 between said collar and nut.

In testimony whereof I have hereunto set my hand this 27th day of August, 1913, in the presence of two witnesses.

GEORGE COOK.

Witnesses:

M. S. CRANDALL, MINERVA CRANDALL. 

